Cranes are essential tools for many construction projects
Allowable Lift Rating. The allowable lift rating for a crane is based either on
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- Load Chart Details Accessories .
- Interpolation between the published values IS NOT permitted
- Transportation, Erection and Dismantling Engineering Requirements
- Erection
- . Personnel who are to be erecting or jumping the crane shall be specifically trained and have a copy of the manufacturer’s procedures.
- Casual inspection is not adequate
- Dismantling
- VII. Hazard Analysis Reference slides 137 - 157 Key Concepts: Hazard Analysis
- Location and Access .
- VIII. Regulations, Standards and Codes
- System of Regulations United States System
- APPENDICES APPENDIX I. Hazard Awareness Figure A-1. Power line clearances
- Normal Voltage, kV (Phase to Phase) Minimum Required Clearance, ft (m) [Note (1)]
- Operation in Transit with Boom or Conveyor Lowered
- Table A-1. Minimum Required Clearances APPENDIX II. Regulations and Standards British, Canadian, and European Systems
- U.S. REGULATIONS STANDARDS Occupational Safety and Health Act (OSHA)
- Other U.S. Regulations Standards
Allowable Lift Rating. The allowable lift rating for a crane is based either on:
Most load rating charts indicate either structural competence or tipping as the basis for the allowable lift. It should be noted that the tipping capacity numbers in the chart are 85% of overturning. This leaves little latitude in estimating the load and/or determining the radius. A weight scale and a tape measure are the most reliable method for determining the capacity. Criteria. All load charts for cranes assume several basic criteria are being met in order to achieve the allowable lift.
The Construction Safety Association of Ontario suggests that as much as 50 percent of the allowable lift capacity of a crane is lost due to a 3 degree out of level condition when utilizing a long boom at a short radius. At 1 degree out of level this loss is 30 percent of the allowable lift capacity of the crane. One degree is approximately 2 inches for outriggers spaced 10 feet apart. A firm base and constantly level conditions are critical for safe crane operation. A study performed by the Society of Automotive Engineers (SAE) indicates that not only is the stability impaired by an out-of-level condition, but the stressed and consequent deflection in the boom is equally as severe. It should be noted that as a crane picks up a load, the radius will increase due to stretch in the pendant cables and deflection in the boom. Load Chart Details Accessories. Load charts can be complex documents listing numerous booms, jibs and other components which may be employed to configure the crane for various tasks. It is critical that the chart used is for the actual configuration of the crane. Load charts show allowable lift capacity at a specified boom length and radius. Interpolation between the published values IS NOT permitted, use the next lower lift capacity value instead, unless otherwise specifically instructed by the manufacturer. Operation in chart areas which have no published value are not permitted. Attachments. This also applies to devices which may be attached to the boom. Most commonly a jib, whether erected or not, when attached to the boom must be considered as part of the load when using the main load line and conversely main load rigging is considered as load when using the jib. All load attaching devices, including the lines, hook/s and block/s must be included as part of the load being lifted. All load charts have extensive notes and warnings. The crane Operator as well as all supervisory personnel associated with rigging and lifting operations must be familiar with these notes. Safety Devices The most important single element in the reduction of crane accidents is the Operator. Crane safety devices are also important elements. Unfortunately, unlimited use of safety devices will not result in a perfectly safe operation. Safety devices may instill a false sense of security. Devices used in place of competence and good judgment on the part of the crane operator contribute to accidents. However, judicious use of effective devices will result in operations that have acceptable risk. Many cranes are equipped with various safety devices as described in detail in the Appendix. There are two common types of safety devices: Load Indicating Device. A load indicating device (LID), indicates the load on the main lifting line. This indicated load, when appropriately modified for parts of line and friction effects, indicates the weight of the lift. If this value exceeds the allowable lift, the device will provide a warning and may also inhibit operation. Load Moment Indicator. A load moment indicator (LMI) is a device which senses both the load and the boom angle, and by correlating the boom angle with the allowable lift at that angle provides a warning and may inhibit operation. Device Effectiveness
Transportation, Erection and Dismantling Engineering Requirements Some cranes have high axle loads that create high ground pressures when they travel. Ground pressures can be even higher during erection and dismantling. Tower cranes and mobile cranes positioned on structures induce significant loads. The contract documents should require the PC/GC/CM to advise the owner or the owner's representative of these crane-imposed loads. These loads and their effects are not always obvious. For this reason, a Professional Engineer shall determine imposed loads, evaluate the effects of those loads and design such supports as may be required. Transportation Mobile cranes and tower cranes require detailed movement planning, including appropriate travel routes with considerations for width, height, and gross vehicle weight limitations. The responsible party should resolve potential problems with the appropriate transportation authorities. This may include securing special permits. Transportation precautions include proper tie-downs that must prevent:
Erection Only qualified personnel shall supervise the erection of the crane. As defined by OSHA, 29 CFR 1926.32(l) states: "Qualified" means one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training and experience, has successfully demonstrated his ability to solve or resolve problems relating to the subject matter, the work, or the project. Before crane erection begins, a qualified person shall carefully inspect the crane for any damage that could affect the safe operation of the crane. Personnel who are to be erecting or jumping the crane shall be specifically trained and have a copy of the manufacturer’s procedures. Boom damage caused by tie downs may not be obvious but can have serious consequences. Such damage is likely to be unobserved during a normal inspection. Once the crane is erected, the damage may not be visible from the ground, so special care must be taken in this regard before erection. Casual inspection is not adequate. All bolted and pinned connections shall be checked to assure that fasteners and keepers meet manufacturer’s requirements and have been correctly installed. For tower cranes, specialty cranes and mobile cranes, an erection plan shall be required. This plan shall be a component of the Crane Safety Plan. It must include any specific procedures needed to carry out the instructions supplied by the crane manufacturer and to adapt them to the particular site conditions. The plan shall include drawings showing clearances to all potential obstructions. The locations for unloading shipped components shall be shown on a site drawing. Local regulations may require third party inspection and/or certification before the crane may be operated. Dismantling Dismantling is not the reverse of crane erection. New permanent structures that are now close to the crane location may create conditions that make dismantling more difficult than assembly. Therefore, it is necessary that a dismantling plan be prepared along with the assembly plan for all tower cranes and for larger mobile and specialty cranes. The plan must follow the manufacturer’s recommendations. Clearances shall be carefully determined. This plan will be a component of the Crane Safety Plan. VII. Hazard Analysis Reference slides # 137 - 157 
Key Concepts: Hazard Analysis
elimination of hazards during design and preconstruction phases.
Good management of crane and rigging operations requires that a hazard analysis not only be performed by the A&E during the design and preconstruction phases but that it be part of the PC/GC/CM's Site Safety Plan. Indeed, a primary goal of a site safety plan and a crane safety plan is to identify and eliminate hazards. Location and Access. Cranes positioned near or attached to a structure can have a major impact on the structure. The allowable loads and their points of application should be clearly defined and approved by a licensed engineer. A&Es must require an analysis of cranes/derricks attached to or supported by the structure. Having large cranes adjacent to a structure may also have a detrimental effect on the structure foundation. The determination of allowable crane locations should reflect concerns for public exposure, adjacent structures, employee and public travel paths, underground structures, previously excavated areas, overhead obstructions and all other factors which impact on safe crane and rigging operations. In addition, load travel paths may have to be defined. Areas that present a severe hazard to personnel should be declared prohibited operating areas or as restricted employee and public access areas. The Public. The A&E must consider the impact of crane operations on the public. Noise, dust, traffic, and other typical nuisances inherent with crane operations may require restricted working hours. These considerations or requirements should be specifically part of the contract documents. ANSI A10.34, Public Protection, as well as other applicable local, state and federal standards apply. The ASCE and, in particular, the CI Committee on Crane Safety have devoted significant efforts to the safety of the public, recognizing that because of the configuration and use of cranes, they present significantly more hazard to the public around a construction site than do other construction operations. Numerous recent crane accidents have resulted in death and injury to the public. Planning crane operations to be safe and to minimally expose the public is crucial to providing for public safety around construction sites. Existing Facilities. Construction within the confines of an existing facility requires that the A&E consider how existing structures and personnel impact crane operations. For example, consideration must be given to such areas as parking, employee and public access, utility lines, railroad tracks and other potential obstructions. Provisions may be required prior to the start of construction for the removal, relocation and/or protection of these areas. These considerations may require constraints on the size and number of cranes and the boom lengths of individual cranes. Power Lines. Power lines do not suddenly appear in the middle of a construction site. Provisions must be made for either deactivating or relocating power lines or imposing restrictions on crane locations. Slide #5 shows that crane contact with electrical lines is a leading cause of fatal crane accidents. The OSHA regulations publish minimum clear distances which must be maintained from power lines of various voltages. The most recent editions of ANSI B30.5, Mobile & Locomotive Cranes, in paragraph 5-3.4.5, recommends that it is advisable to perform the work so that there is NO possibility of contact with power lines and provides illustrations emphasizing this point. This standard also establishes procedures in 5-3.4.5.2 for crane operations near de-energized and grounded power lines and in 5-3.4.5.3, for crane operations within the erected/fully extended boom length of the prohibited zone, with power lines energized. These recommended procedures should be instituted on every construction site as policy and be a part of every lift plan. Applicable OSHA and ANSI B30 standards, B30.5-3.4.5.2, 5-3.4.5.3, and 5-3.4.5.4, in particular, are more stringent than federal standards and provide more guidance for safe operation of cranes in the vicinity of power lines. Size of Components. Lifting of major components, such as boilers or large air conditioning units should be analyzed to eliminate the hazards associated with unusual weights, centers of gravity, heights or position in the structure. Controlling the size of the component or establishing a location or placement sequence more favorable to placement can result in significant savings in crane and rigging costs as well as reducing any hazard. VIII. Regulations, Standards and Codes Reference Module 2, slides # 1- 22 
Key Concepts: Regulations, Standards and Codes
System of Regulations United States System The system of regulations, standards, and codes developed in the United States allows significant flexibility, permitting the user to define specific requirements within its framework. Regulations In the United States, regulations have been promulgated by legislative or regulatory agencies that set forth minimum requirements. This results in regulations that require a minimum standard for the protection of individuals and the public at large. In practice, such minimum standards are frequently exceeded in order to have machines that are safer and easier to use. Consensus Standards In addition to the federal, state, or local regulations, there are a significant number of consensus standards. These standards reflect general agreement of an industry representative group. Standards produced under the consensus system, while generally reflecting a level of performance significantly above the minimum regulation standard, reflect the state of the industry or "best practice." Consensus Standards usually lag behind the state of the art in the industry. Standard Specifications In addition to the consensus standards there are a significant number of standard specifications. These specifications are produced by manufacturers or manufacturer's associations as well as user associations such as the Associated General Contractors (AGC). These standard specifications provide an industry-wide standard when regulations or consensus standards are not available, not sufficiently detailed or are inappropriate to serve as a specification in a contract or a purchase document. These standard specifications serve as a purchaser's benchmark for quality in a service or product. Examples of these standard specifications come in the AGC's Manual of Accident Prevention, the USACE's Accident Prevention Manual and most recently, the Department of Energy's Crane and Rigging Plan. These are, in effect, standard specifications for performance which require a level that is higher than the regulatory requirements and may exceed many of the consensus standards. These standard specifications may even reflect a state of the art and may require levels well above industry average. In addition to the preceding documents, many professional organizations produce a code of practice that is a standard specification for the guidance of their members. Recent Trends There is movement toward adopting consensus standards as regulatory law whenever a consensus standard is available for an area that needs regulation. There are now instances in the U.S. system where regulatory agencies have adopted consensus standards. The advantage to adopting consensus standards as regulatory is that it reflects a consensus of industry. The disadvantage is that consensus standards represent an industry average which may put an undue burden on those below the average because it will require closer adherence to state of the industry by all members of the industry. This trend also places a significant burden on the standards-producing organizations to create and maintain their standards not only as state of the industry but as possible regulations. See Appendix for more detailed information on regulations and standards. APPENDICES APPENDIX I. Hazard Awareness Figure A-1. Power line clearances 
This area should be avoided This area should be avoided Danger zone area (see General Note)
GENERAL NOTE: For minimum radial distance of danger zone, see Table A-1 Table A-1. Minimum Required Clearances APPENDIX II. Regulations and Standards British, Canadian, and European Systems In Britain, Canada, and Europe, the distinction between regulatory and consensus standards does not exist. They develop standards through technical committees such as the British Standards Institute and the Canadian Standards Association. These committees may have less input from industry representatives than in the U.S system. Compliance with British and Canadian standards is not a voluntary act such as compliance with ANSI or ASTM Standards may be in the US. It is compulsory. The final result is a regulation in the British and Canadian systems that reflect a state of the industry rather than the minimum requirements. Although this system may set a higher minimum for operating performance, it does not benefit from the use of a consensus method for developing the standards. The system also inhibits early standards for "state of the art" developments because most "state of the art" developments should not yet be mandatory. In the British, Canadian, and for the most part European systems there is an advisory document usually referred to as a guide which that is designed to assist and implement the standard and generally provides a step by step "how to comply" instruction. U.S. REGULATIONS & STANDARDS Occupational Safety and Health Act (OSHA)
Code of Federal Regulations, General Industry Standards, Title 29, Part 1910 Code of Federal Regulations, Construction Standards, Title 29, Part 1926 Safety and Health Regulations for Marine Terminals, Title 29, Part 1917 Safety and Health Regulations for Longshoring, Title 29, Part 1918 Other U.S. Regulations & Standards
Local Law
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